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1.
ACS Cent Sci ; 5(7): 1187-1198, 2019 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-31404239

RESUMO

The development and integration of Single-Molecule Magnets (SMMs) into molecular electronic devices continue to be an exciting challenge. In such potential devices, heat generation due to the electric current is a critical issue that has to be considered upon device fabrication. To read out accurately the temperature at the submicrometer spatial range, new multifunctional SMMs need to be developed. Herein, we present the first self-calibrated molecular thermometer with SMM properties, which provides an elegant avenue to address these issues. The employment of 2,2'-bipyrimidine and 1,1,1-trifluoroacetylacetonate ligands results in a dinuclear compound, [Dy2(bpm)(tfaa)6], which exhibits slow relaxation of the magnetization along with remarkable photoluminescent properties. This combination allows the gaining of fundamental insight in the electronic properties of the compound and investigation of optomagnetic cross-effects (Zeeman effect). Importantly, spectral variations stemming from two distinct thermal-dependent mechanisms taking place at the molecular level are used to perform luminescence thermometry over the 5-398 K temperature range. Overall, these properties make the proposed system a unique molecular luminescent thermometer bearing SMM properties, which preserves its temperature self-monitoring capability even under applied magnetic fields.

2.
Chem Commun (Camb) ; 53(62): 8660-8663, 2017 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-28718476

RESUMO

A planar tetradentate 3,6-bis(2-pyrimidyl)-1,2,4,5-tetrazine (BpymTz) templating chelate affords the formation of an unprecedented BpymTz˙- radical anion bridged {Ni} complex. Detailed magnetic measurements performed on the isolated air stable [Ni(BpymTz˙-)Cl6(DMF)8]Cl·0.5(H2O) compound reveal strong ferromagnetic NiII-BpymTz˙- interactions with a coupling constant of J = 98.84 cm-1.

3.
Chem Commun (Camb) ; 52(70): 10680-3, 2016 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-27507123

RESUMO

Studies of three related Cd(II) systems (a discrete [Cd(II)2] unit, a one-dimensional [Cd(II)2]n coordination polymer and a Cd(II)-based MOF) all derived from the ligand 2,4,6-tris(2-pyrimidyl)-1,3,5-triazine, reveal an exceptionally rare example of (113)Cd-(113)Cd J coupling in the polymer that is detectable by solid-state NMR ((2)JCd-Cd = ∼65 Hz).

4.
Chemistry ; 22(6): 1931-1936, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26669481

RESUMO

After more than 50 years, the synthesis and electronic structure of the first and only reported "U0 complex" [U(bipy)4 ] (1) has been reinvestigated. Additionally, its one-electron reduced product [Na(THF)6 ][U(bipy)4 ] (2) has been newly discovered. High resolution crystallographic analyses combined with magnetic and computational data show that 1 and its derivative 2 are best described as highly reduced species containing mid-to-high-valent uranium ligated by redox non-innocent ligands.

5.
Chemistry ; 21(28): 10014-8, 2015 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-26095155

RESUMO

The direct, nucleophilic imidation of acetanilide derivatives has been performed under mild, iodine(III)-mediated or -catalyzed conditions, employing lithium triflimide as the nitrogen source. The reaction exhibits exclusive regioselectivity for the para position and shows a good tolerance for varied functional groups at both the ortho or meta positions. Preliminary mechanistic data suggest that the LiNTf2 reagent plays a key role in the reactivity.

6.
Chem Commun (Camb) ; 51(46): 9547-50, 2015 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-25970021

RESUMO

Three novel 1D, 2D and 3D coordination polymers were successfully isolated using nitrogen based 3,6-bis(2'-pyrimidyl)-1,2,4,5-tetrazine (BPymTz) and 2,4,6-tris(2-pyrimidyl)-1,3,5-triazine (TPymT) ligands with Ag(I) ions. The formation of these supramolecular assemblies was templated through anion-π-system interactions.


Assuntos
Complexos de Coordenação/química , Pirimidinas/química , Prata/química , Triazinas/química , Ânions/química , Elétrons , Ligantes , Polímeros/química
7.
Chemistry ; 21(16): 6144-9, 2015 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-25760516

RESUMO

An unprecedented trinuclear heteroleptic Ag(I) complex was isolated using a stable multidentate 2,4,6-tris(2-pyrimidyl)-1,3,5-triazine (TPymT) ligand. The obtained compound is an efficient catalyst for the direct aziridination of terminal olefins.

8.
Org Lett ; 15(7): 1764-7, 2013 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-23534500

RESUMO

Direct triflation of acetanilide derivatives with silver triflate has been accomplished under mild iodine(III)-mediated oxidative conditions. The reaction shows excellent regioselectivity for the para position and tolerates a range of ortho and meta substituents on the aromatic ring. This method is also compatible with the preparation of arylnonaflates in synthetically useful yields.

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